CN104252838B - Display driver, display drive method and display device - Google Patents
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Abstract
Provide a kind of for according to the display driver of the gray value driving data line of pixel in display unit.Described display driver includes: corrected value signal generating unit, for based on scan line be corresponding in the video data of pixel in every scan line each described gray value count video data quantity, and based on described count results generate described video data corrected value；And driving signal generating unit, it is corrected processing to described video data for the corrected value generated by described corrected value signal generating unit by use, and generates data wire driving signal in order to drive every described data wire based on the video data after correction.
Description
Technical field
The present invention relates to a kind of display driver, display drive method and display device, particularly relate to display
Unit actuation techniques, which provided data wire and scan line, and in described data wire and described scan line
Each cross point formed pixel.
Background technology
As the display floater for showing image, it is thus well known that there is use Organic Light Emitting Diode
(OLED) display device, the display device etc. of use liquid crystal display (LCD).In many
In the case of, display device includes display unit, which provided data wire and scan line, every data
Line is commonly connected to the multiple pixels along column direction arrangement, and every scan line is commonly connected to along row
Multiple pixels of direction arrangement, and picture is formed in each cross point of described data wire and described scan line
Element.
Therefore, in so-called progressive scan example, scan line driver is sequentially selected scan line also
And datawire driver is to each data wire output data line of the pixel corresponding to selected scan line
Drive signal, thus control each point and be shown as pixel.
The Japanese patent application of Publication No. H9-232074 discloses, when scanning is from a scan line
When another scan line order switching, all scan lines are once connected to the technology of reset potential,
Thus lighting delay preventing the pixel caused by the parasitic capacitance of display floater.
The Japanese patent application of Publication No. 2004-309698 discloses, when providing to data electrode
During display signal, all data electrodes are connected to reset potential and are subsequently attached to predetermined potential
Technology, thus reduce crossing of display signal and rush and undershoot.
Such as, in the example of passive OLED display device, when selecting and driving, there is mixing gray scale
(gradation), during a scan line of pixel, there occur a phenomenon in which, i.e. relatively low bright when having
During the anode drive signal at stop spent, the anode voltage of this anode drive signal crosses punching.This may cause
There is on display image local the brightness higher than original brightness, and the display of described display image is uneven
Even.
Summary of the invention
In view of the foregoing, the present invention provides a kind of display driver, display drive method and display device,
It can reduce the brightness flop caused due to display overshoot and suppress brightness irregularities (display
Uneven).
According to an aspect of the present invention, it is provided that the display of a kind of data wire for driving in display unit
Driver, described display unit includes that data wire, every data line are commonly connected to and arranges along column direction
Multiple pixels；Scan line, every scan line is commonly connected to the multiple pixels arranged in the row direction；
And formed with corresponding to described data wire and the pixel in each cross point of described scan line, described display
Driver drives described data wire according to the gray value of described pixel.Further, described display driver
Including: corrected value signal generating unit, being used for based on scan line is corresponding to the display of pixel in every scan line
The each described gray value counting video data quantity of data, and generate described based on described count results
The corrected value of video data；And driving signal generating unit, for being generated by described corrected value by use
Described video data is corrected processing by the corrected value that unit generates, and based on the video data after correction
Generating data wire drives signal in order to drive every described data wire.
In the case of being applied to every data line according to the signal of grey scale pixel value, due to other pixel
Quantity and the impact of gray scale of other pixel, be applied on the signal of a described pixel be likely to occur
Cross punching.In the present invention, it is not intended that eliminated punching itself, and be intended to make respective pixel original with it
Intensity LEDs.To this end, drive signal to be applied to respective pixel the data wire after correction.
Specifically, the video data representing each pixel grey scale is corrected, and based on showing after correction
Show that data genaration data wire drives signal.Display according to gray scale each in the video data of respective scan line
Data bulk determines video data to be corrected and correcting value thereof.Therefore, it is possible to suitable correcting value pair
Corresponding to additionally occurring because crossing punching showing that the video data of uneven part is corrected processing.
In described display driver, described corrected value signal generating unit can be according to each described gray value
Video data quantity obtains correcting value, and by using the correcting value of each described gray value obtained
Calculate the correcting value of the gray value higher gray value more corresponding than the correcting value obtained.
Depend on the video data quantity of relatively low gray scale in same scan line, showing of the higher gray scale of overshoot effect
Show district's brightness.Therefore, according to the video data quantity of each described gray value, by using described correction
Amount determines the video data correcting value of higher gray scale.
In described display driver, shown the video data quantity of each described gray value by use
And the inquiry table of corresponding relation between correcting value, described corrected value signal generating unit can be according to each described ash
The count results of the video data quantity of angle value generates corrected value.
By the video data quantity of each described gray value and the correcting value of correspondence thereof are stored inquiry
Table, can obtain, in conjunction with inquiry table, the correcting value that the video data quantity of each gray value is corresponding.
In described display driver, there is the constant electricity of persistent period corresponding to each described gray value
Stream signal can drive signal to be applied to described data wire as described data wire, and looks into described in being stored in
Correcting value in inquiry table can correspond to shorten the value of described persistent period.
According to this configuration, even if brightness increases owing to crossing punching, it is shortened by constant current and is applied to
The persistent period of respective pixel can reduce the brightness on display image.
In described display driver, it is preferable that the correcting value stored in described inquiry table and video data
One or both in quantity is rewritable.Therefore, it can according in display unit specification change with
Suitable correcting value updates inquiry table.
In described display driver, it is preferable that have corresponding to each described gray value persistent period
Constant current signal drives signal to be applied to described data wire, and described corrected value as described data wire
Signal generating unit is only corrected place to the video data with the gray value that the corresponding persistent period is more than threshold value
Reason.
By doing so it is possible, be possible to prevent low gray areas (black display region) to be become by correction process
The darkest.
In described display driver, described driving signal generating unit can be by limiting described correcting value
It is corrected processing so that the gray value of the video data after correction goes above corresponding to following correction closely
After video data gray value below the value of gray value.
According to the configuration, it is possible to by preventing the calibrated process disappearance of the difference between gray scale from keeping display
Gray scale in image.
According to another aspect of the present invention, it is provided that a kind of for according to the gray value of pixel in display unit
The display drive method of driving data line, described display unit includes data wire, and every data line is by jointly
It is connected to the multiple pixels along column direction arrangement；Scan line, every scan line is commonly connected to along row side
Multiple pixels to arrangement；And formed with each intersection corresponding to described data wire and described scan line
The pixel of point, described display drive method includes: based on scan line for corresponding to pixel in every scan line
Video data in each described gray value counting video data quantity, and raw according to described count results
Become the corrected value of described video data；And by using the corrected value generated that described video data is entered
Row correction process, and generate data wire driving signal in order to drive every institute based on the video data after correction
State data wire.
According to the configuration, it is possible to rush institute by the mistake in reason data line signal at correction video data
The brightness flop caused.
According to another aspect of the present invention, it is provided that a kind of display device, including: display unit, including number
According to line, every data line is commonly connected to the multiple pixels along column direction arrangement；Scan line, sweeps for every
Retouch line and be commonly connected to the multiple pixels arranged in the row direction；And formed with corresponding to described data wire
Pixel with each cross point of described scan line；Display driver, is used for according to described corresponding to pixel
Gray value drive every described data wire；And scan line driver, for applying to sweep to described scan line
Retouch signal.Further, described display driver includes: corrected value signal generating unit, for based on scanning
Line is to count video data corresponding to each described gray value in the video data of pixel in every scan line
Quantity, and the corrected value of described video data is generated based on described count results；Single with driving signal to generate
Unit, for by using the corrected value generated by described corrected value signal generating unit to carry out described video data
Correction process, and generate data wire based on the video data after correction and drive signal in order to described in driving every
Data wire.
It is to say, described display device includes above-mentioned display driver.
According to above-mentioned configuration, signal cancellation can be driven to drive signal due to data wire by correction data line
Excessively rush cause visible brightness change.Therefore, it can reduce and show uneven (brightness irregularities),
And improve display quality.
Accompanying drawing explanation
By description to the embodiment of the present invention in conjunction with the following drawings, the purpose of the present invention and feature will become
It is clear that wherein:
Fig. 1 is the block diagram of an example of the display device according to one embodiment of the invention；
Fig. 2 A and Fig. 2 B is respectively the controller IC according to an embodiment and the block diagram of timing controller；
Fig. 3 A to Fig. 3 C is and to inquire about according to gray scale chart, the anode drive output of an embodiment for explanation
The schematic diagram of table；
Fig. 4 A to Fig. 4 C is for illustrating to show the schematic diagram of generation brightness flop situation on image；
Fig. 5 is to cause brightness flop to cross the schematic diagram of punching for explanation；
Fig. 6 A to Fig. 6 E is the schematic diagram for brightness flop reason is described；
Fig. 7 A to Fig. 7 F is the schematic diagram illustrating how to create checking list according to an embodiment；
Fig. 8 A to Fig. 8 D is that the correction according to an embodiment is for the schematic diagram that pulse width variation is described；
With
Fig. 9 to Figure 11 is the flow chart of the correction table creation process according to an embodiment.
Detailed description of the invention
It is bonded the accompanying drawing of a present invention part, below the embodiment of the present invention is described.
<display device and the configuration of display driver>
Fig. 1 shows display device 1 according to an embodiment and grasps for controlling the display of this display device 1
The microprocessing unit (MPU) 2 made.Described display device 1 include the display unit 10 as display screen,
Controller IC (IC) 20 and cathode drive 21.
Described display unit 10 includes data wire DL (specifically, DL1～DL256), scan line SL
(specifically, SL1～SL128) and on the cross point of described data wire DL and described scan line SL
The pixel arranged.Such as, 256 data line DL1～DL256 and 128 scan lines it are provided with
SL1～SL128.Therefore, arrange 256 pixels in the horizontal direction, vertically disposed 128
Individual pixel.Therefore, described display unit 10 has 256 × 128=32768 pixel as constituting display
The pixel of image.In the present embodiment, each pixel is made up of the self-emission device using OLED.Separately
Outward, the quantity of the quantity of pixel, the quantity of data wire and scan line is merely exemplary.
In 256 data line DL1～DL256 every is commonly connected to along described display unit 10
128 pixels that column direction (vertical direction) is arranged.Additionally, in 128 scan lines SL1～SL128
Each be commonly connected in the row direction 256 pixels that (horizontal direction) arranges.When based on aobvious
Registration is applied to selected scan line SL according to the signal that drives of (brightness value) from data wire DL
During 256 pixels, each pixel of institute's route selection is actuated to brightness (gray scale) based on video data and sends out
Light.
Described controller IC 20 and described cathode drive 21 are in order to drive the aobvious of described display unit 10
Show.Described controller IC 20 includes driving control unit 31, video data memory element 32 and anode to drive
Dynamic device 33.Described anode driver 33 driving data line DL1～DL256.In the present embodiment, institute is worked as
When stating the pulse signal of the pulse width driving control unit 31 to apply to have corresponding grey scale, described anode drives
Dynamic device 33 is in the introversive described data wire DL of duty cycle (On-duty period) of described pulse signal
Every output constant current.In the following description, described pulse signal and be applied to every described number
It is commonly referred to " data wire driving signal " according to the constant current signal of line DL, but, distinguish when concrete
Time, the data wire as pulse signal drives signal to be represented as or is referred to as " anode command signal ", and
It is applied to the constant current signal of every described data wire DL be represented as or be referred to as that " anode driver is defeated
Go out signal ".
Described driving control unit 31 carries out instructing and indicated data communication with MPU2, and according to this instruction
Control display operation.Such as, when receiving display sign on, described driving control unit 31 is carried out
Time set, and allow described cathode drive 21 to start to scan described scan line SL.Further,
The scanning that described driving control unit 31 and described cathode drive 21 are carried out is synchronizedly from described anode
Driver 33 drives 256 data line DL.
For being driven described data wire DL by described anode driver 33, described driving control unit
The video data received from described MPU2 is stored in described video data memory element 32 by 31,
And based on described video data with the scanning carried out by described cathode drive 21 synchronizedly to described
Anode driver 33 provides data wire to drive signal (anode command signal).Therefore, described anode drive
Device 33 drives signal (anode driver output letter to the data wire of described data wire DL output corresponding grey scale
Number).By this control, each pixel in selected row, i.e. carried by described cathode drive 21
The scanning of confession scan line SL selected by signal, is driven to emit light.By this way, all of row
It is sequentially driven luminescence, thus is realized the display of a two field picture.
Described cathode drive 21 plays the effect of scan line driver, for described scan line SL
One end applies scanning signal.Described cathode drive 21 is configured such that outfan Q1～Q128 is respectively
It is connected to one end of scan line SL1～SL128.By along scanning direction SD shown in Fig. 1 from outfan Q1
The scanning signal of level, scanning is selected to be performed with order selection to outfan Q128 Sequential output described
Scan line SL1～SL128.
Fig. 2 A shows that the controller IC 20 as display driver configures, and especially illustrate in detail
Drive control unit 31.As shown in Figure 2 A, described driving control unit 31 include MPU interface 41,
Instruction decoder 42, oscillating circuit 43 and timing controller 44.
Described MPU interface 41 is to carry out the interface circuit of various communication with MPU2.Specifically, described
MPU interface 41 allows send video data or command signal to described MPU2 and connect from described MPU2
Receive video data or command signal.The command signal that described instruction decoder 42 will send from described MPU2
It is stored in internal register (not shown) and this command signal is decoded.Then, described instruction decoding
Device 42 notifies the information of described timing controller 44 necessity, holds with the content according to described command signal
Row operation.It addition, the video data sent from described MPU2 is stored institute by described instruction decoder 42
State in video data memory element 32.
Described oscillating circuit 43 generates for showing clock signal CK driving control.Described clock signal
CK is provided to described video data memory element 32 and is used as data write and read operation
Clock.It addition, described clock signal CK is provided to described timing controller 44 and is used for its operation.
When described timing controller 44 arranges the driving of scan line SL of display unit 10 and data wire DL
Between.Then, described timing controller 44 output cathode driver control signal CA is to perform by described the moon
The row scanning that driver 21 is carried out.
Additionally, described timing controller 44 drives signal (sun to described anode driver 33 output data line
Pole command signal) to carry out the driving of data wire DL.To this end, described timing controller 44 is from described aobvious
Show that data storage cell 32 reads video data, and generate data wire driving signal based on this video data.
Therefore, with synchronised sweep time of respective scan line SL, described anode driver 33 is to selected row
The output of each pixel drives the constant current of signal corresponding to data wire.
In the present embodiment, as it can be seen, described timing controller 44 specifically includes corrected value signal generating unit
44a and driving signal generating unit 44b, as the configuration of described anode driver 33.
Described corrected value signal generating unit 44a is each picture to be applied to every scan line SL based on scan line
Variant gray value counting video data number in the video data of element, and based on described count results
Generate the corrected value of described video data.Described driving signal generating unit 44b is by using by described school
Described video data is corrected processing by the corrected value generated on the occasion of signal generating unit 44a, and based on correction
After video data generate data wire drive signal (anode command signal) in order to drive every described data wire
DL。
Fig. 2 B shows corrected value signal generating unit 44a and the example of driving signal generating unit 44b concrete configuration
Son.As shown in Figure 2 B, described corrected value signal generating unit 44a includes inquiry table memory element 56, correction
Table generative circuit 57 and checking list memory element 58.It addition, described driving signal generating unit 44b bag
Include buffer 52, selector 53 and 59, gray scale chart memory element 54, adder 55, latch cicuit
60 (specifically, 60-1～60-256), enumerator 61 and comparator circuit 62 are (specifically,
62-1～62-256).Regularly generative circuit 51 controls constitute described corrected value signal generating unit 44a and described drive
The operation timing (operation timing) of each parts of dynamic signal signal generating unit 44b.
First, the operation in addition to correction process will be illustrated in conjunction with Fig. 2 B.Timing controller
44 will be stored in the video data in video data memory element 32 based on scan line is stored in buffer 52,
And generate data wire driving signal based on it.Specifically, read a line from video data memory element 32 to sweep
Retouch the video data (video datas of 256 pixels) of line, and it is slow to be deposited into (being temporarily stored to)
Rush device 52.Each video data is, such as, each pixel 4 bit data, it represents in 16 gray scales
One.The buffering video data of one horizontal scanning line, the i.e. video data of 256 pixels, with pixel (4
Position) mode is provided to selector 53.Selector 53 selects and output gray level table according to 4 gray values
The objective count value of storage in memory element 54.
Such as, Fig. 3 A shows the gray scale chart of storage in gray scale chart memory element 54, and wherein 4 two are entered
Data processed are associated with objective count value respectively.Fig. 3 A is also shown for gray value and pulse width for
Reference, but it is not necessary that they are stored as the table data of reality.Gray value represents 16 gray values,
Each by " 0/15 " to " 15/15 " expression, it is respectively provided with 4 bit binary data " 0000 " and arrives " 1111 ".
In this case, " 0/15 " is corresponding to having the black display gray scale of minimum brightness, and " 15/15 "
Corresponding to having the white displays gray scale of high-high brightness.
Pulse width correspondence objective count value controls pulse when data wire drives signal (anode command signal)
The duty cycle of signal, and be a period of time of exporting as anode driver output signal of constant current.
In the present embodiment, corresponding 0.25 microsecond of counting of objective count value.Such as, if object count
Value is 480, then pulse width is 120 microseconds.
Selector 53 is read by the gray scale chart of storage in reference gray level table memory element 54 and is exported correspondence
Objective count value in 4 video datas (gray scale).Such as, if 4 video datas are " 1100 "
(12/15 gray value), the then objective count value of output 200.Objective count value is by by video data
Grayvalue transition becomes time value to obtain, and substantially corresponding to the value of video data gray scale.If
Do not carry out any correction, then the objective count value exported from selector 53 is essentially latched circuit 60 and locks
Deposit.In the to be described example being corrected, by adder 55 to exporting from selector 53
Objective count value performs correction calculation and processes.
Latch cicuit 60 includes multiple latch cicuit (these realities being set to correspond to an each pixel of horizontal scanning line
Execute 256 latch cicuit 60-1～60-256 in example).Selected by video data based on a horizontal scanning line
Objective count value is latched by each latch cicuit 60.Therefore, each object count of the pixel of a horizontal scanning line
Value is introduced in corresponding latch cicuit 60-1～60-256.Each latch cicuit 60-1～60-256 is latched
Objective count value compares with the count value of each comparator circuit 62-1～62-256 Counter 61.Its
Result is, it is thus achieved that the data wire of every data line drives signal (anode command signal).
In conjunction with Fig. 3 B, this operation will be described in more details.Enumerator 61 is according to clock signal CK
Repeatedly it count down to predetermined upper limit value.This higher limit is arranged to the time period corresponding to a horizontal scanning line SL
Value.The output of comparison circuit 62-1～the 62-256 time point when the count value of enumerator 61 resets rises
To high (H) level.Then, when count value reaches the objective count value after latching, corresponding the most electric
The output on road 62 is reduced to low (L) level.
Such as, if the objective count value latched by latch cicuit 60 x is Dpw1, then from accordingly than
Relatively device circuit 62-x obtains and compares output ADT1.If additionally, the target latched by latch cicuit 60 y
Count value is Dpw2, then obtain from corresponding comparator circuit 62-y and compare output ADT2.Finally,
Comparator circuit 62-1～62-256 output has the pulse of the pulse width corresponding to video data gray value,
Objective count value is latched i.e., respectively by latch cicuit 60-1～60-256.
Above-mentioned each comparison exports as the data wire driving signal of data wire DL1～DL256 every described
(anode command signal) is provided to anode driver 33.The pulse signal of signal is driven at each data wire
Duty cycle in, anode driver 33 to every described data wire DL1～DL256 export constant current
Signal (anode driver output signal).Such as, by driving signal to switch on and off according to data wire
The electric current output of constant current source, anode driver 33 output anode driver output signal.
It is above timing controller 44 and does not consider the basic operation of correction.In the present embodiment, with scan line
Based on, checking list generative circuit 57 creates for correcting mesh by using inquiry table memory element 56
The checking list of mark count value (that is, corresponding to the time value of gray scale), and it is stored to checking list storage
In unit 58, wherein said objective count value corresponding to be applied to respective scan line SL in pixel show
Registration evidence.Then, corresponding to the corrected value (count correction value being described below) of each pixel by selecting
Select device 59 to read, and be applied to adder 55.Objective count value and corrected value are carried out by adder 55
Calculation process, thus correct objective count value.
For correct operation, inquiry table shown in Fig. 3 C is stored in inquiry table memory element 56.
As shown in Figure 3 C, in this inquiry table, number of gray values is associated with correcting value.Fig. 3 C also show
Pulse width correction amount corresponding to correcting value is for reference, it is not necessary, however, to be stored as reality
Table data.Number of gray values represents corresponding to having phase in the video data of pixel on a horizontal scanning line
Video data quantity with gray scale.
According to having the video data quantity of same grayscale value, described correcting value is to be applied to corresponding gray scale
The correcting value of the original object count value of value.Described correcting value is for obtaining the counting school that will be described below
On the occasion of.1 counting (=0.25 microsecond) of the corresponding objective count value of correcting value " 1 ".Correcting value is deposited
Storage is negative value, example as directed "-4 ", "-8 " ..., "-24 ", and it represents that constant current applies
The time period reduced to data wire DL.
Pulse width correction amount by changing into the correction that data wire drives the pulse width of signal by correcting value
Measure and obtain.In other words, negative correcting quantity becomes and actually applies the time period that constant current is reduced.Under
The correct operation using inquiry table will be described in detail by face.
Such as, according to the instruction from MPU2, number of gray values and correcting value in inquiry table are to weigh
Write.Such as, when the power is turned on, MPU2 looks into controller IC 20 transmission table data with for rewriting
Ask the command signal of table.Furthermore it is possible to arranged the gray scale chart shown in Fig. 3 A by MPU2 so that permissible
When such as power on, the gamma characteristic according to display unit 10 calculates objective count value.In this situation
Under, when the power is turned on, inquiry table and gray scale chart can be set.
<display occurs the description of brightness flop>
The present embodiment as above is corrected, the reason that be corrected is mentioned below.
Fig. 4 A shows the embodiment of the display image on display unit 10.In the present embodiment, pass through
Background area Ag1 is set to the gray value of 8/15 and middle section Ag2 is set to the gray scale of 4/15
Value performs display.Such as, middle section Ag2 is being arranged on relatively low-light level and will be around middle section
In the case of the background area Ag1 of Ag2 is arranged on the brightness of intermediate grey values, it is possible to there will be one
Phenomenon, i.e. region AR1 and region AR2 in background area Ag1 shown in Fig. 4 A have different ashes
Degree.It is to say, by the region AR2 (left side of middle section Ag2 and right side area) of dotted line limit
Brightness may become higher than the brightness of background area other parts, this can cause showing uneven.This
Phenomenon is owing in the AR2 of region, the data wire of pixel drives signal (anode driver output signal) to cross punching
Caused.
Described punching excessively will be illustrated.Fig. 4 B schematically shows four row continuous print scan lines
SLy～SLy+3 and data wire DLp, DLu, DLq.Scan line SLy, its institute of the every behavior in SLy+1
Pixel is had to constitute the scan line of background area Ag1.Scan line SLy+2, its part of every behavior in SLy+3
Pixel constitutes the scan line of middle section Ag2.It addition, data wire DLp, every in DLu is for including
Constitute the data wire of the pixel of middle section Ag2, and data wire DLq is not for including constituting middle section
The data wire of the pixel of Ag2.Fig. 4 C shows data wire DLp, and the data wire of DLq drives signal (sun
Pole command signal) and it is applied to the scanning signal of scan line SLy～SLy+3.It addition, data wire DLu
Data wire drive the data wire of signal and data wire DLp to drive signal to be identical.
When corresponding scan line SL is in selected state, it is applied to the scanning signal of every horizontal scanning line SL
For having the signal of L level.Fig. 4 C shows that scan line SLy～SLy+3 are horizontal scanning line SL pair
The state that each time period answered sequentially is selected.Additionally, within the time period that arrow RS represents, institute
Scanning signal is had to be all set to L level.This time period is the driving side of so-called negative electrode repositioning method
Reset cycle in method.In described negative electrode repositioning method, when scanning is switched to from a horizontal scanning line
During one horizontal scanning line, all scan lines are the most once connected to reset potential, thus decrease pixel light and launch
The delay started.
For the anode command signal of data wire DLq, equal owing to being connected to all pixels of data wire DLq
Belong to background area Ag1, when choosing scan line SLy～SLy+3 respectively, there is 8/15 gray value corresponding
The pulse signal of pulse width be applied to each pixel of data wire DLq.Duty at pulse signal
In cycle, constant current is applied to data wire DLq.
Meanwhile, be connected to the pixel of data wire DLp (with data wire DLu) include background area Ag1 and
The pixel of middle section Ag2.Therefore, when elected middle scan line SLy and SLy+1, there is 8/15 ash
The pulse signal of the pulse width that angle value is corresponding is applied to data wire as anode driver output signal
DLp, when elected middle scan line SLy+2 and scan line SLy+3, has the pulse that 4/15 gray value is corresponding
The pulse signal of width is applied to data wire DLp as anode driver output signal.
Fig. 5 shows that the data wire of data wire DL drives signal.As reference, A and B in Fig. 5
Respectively impulse waveform is illustrated as the data wire in the case of 0/15 and 15/15 gray value and drives signal.At figure
In 5, C shows 4/15 gray scale in the middle section Ag2 of data wire DLp and DLu shown in Fig. 4 C
The anode command signal corresponding to pixel of value, D shows the data wire DLp shown in Fig. 4 C, DLu, DLq
Background area Ag1 in anode command signal corresponding to the pixel of 8/15 gray value.
Anode command signal C shown in response diagram 5, the anode driver output letter that E represents as shown in Figure 5
Number it is applied to data wire DL.Further, anode command signal D shown in response diagram 5, by Fig. 5 institute
Show that the anode driver output signal that F represents is applied to data wire DL.Additionally, at anode shown in Fig. 5
In the waveform of driver output signal E and F, rising edge is to tilt, and this is considered as due to data wire
The impact of wiring capacitance.
In Figure 5, G shows anode driver output letter corresponding for the D of anode command signal shown in Fig. 5
Number another example, be similar to anode driver output signal F shown in Fig. 5.But, once anode
The waveform (current potential of data wire) of driver output signal G declines, and its reaction is to occur rushing OS.
The waveform of anode driver output signal F shown in Fig. 5 corresponds to anode driver output signal at Fig. 4 C
The waveform in time period H1 in shown anode command signal, and the output letter of anode driver shown in Fig. 5
The waveform of number G is corresponding to the anode driver output signal time in anode command signal shown in Fig. 4 C
Waveform in section H2.
It is to say, data wire DLp, the anode driver output signal of 8/15 gray value of DLu, DLq
(current potential of data wire) becomes the output of anode driver shown in Fig. 5 within the H1 time period shown in Fig. 4 C
The waveform of signal F, and the anode driver output signal (data wire of 8/15 gray value of data wire DLq
Current potential) within the H2 time period shown in Fig. 4 C, become anode driver output signal G shown in Fig. 5
Waveform.Therefore, the anode driver output signal of the pixel in being applied to region AR2 shown in Fig. 4 A
In, as shown in the G of Fig. 5, occurred rushing OS.Therefore, the brightness of region AR2 rushes OS owing to crossing
Become higher than original brightness, be visually recognized to be display uneven.
Cross rush OS occur reason as follows.Fig. 6 A and Fig. 6 B schematically shows data wire DLp, DLu,
DLq, scan line Sly+2 and be positioned at pixel Gp in its cross point, the equivalent circuit of Gu, Gq.Attached
In figure, organic electroluminescence pixel is represented by Diode symbol.Additionally, also illustrate the wiring electricity of data wire DL
Resistance element r1, the routing resistance element r2 and organic electroluminescence pixel Gp of scan line SL, Gu, Gq's
Parasitic capacitance CEL。
Within the H2 time period, the state shown in Fig. 6 A becomes the state shown in Fig. 6 B.Such as Fig. 6 A institute
Showing, at the first half section of H2 time period, all of data wire DLp, DLu, DLq are carried out with constant current
Drive, and the dotted arrow circulation that electric current is as shown in Figure 6A.For 4/15 gray value and 8/15 gray scale
For the pixel of value, the time period length applying electric current is different (C and D shown in Figure 5).
Therefore, as shown in Figure 6B, in the second half section of H2 time period, electric current flows through (being represented by dotted arrow)
Data wire DLq, pixel thereon is driven with 8/15 gray value, but do not have electric current flow through (by <
Close represent) data wire DLp, DLu, pixel thereon is driven with 4/15 gray value.
Within the H2 time period, the current potential of Fig. 6 B midpoint NDa reduces as shown in Figure 6 D.In other words, when
From status transition shown in Fig. 6 A to shown in Fig. 6 B during state, the electric current flowing through scan line Sly+2 reduces,
Thus the current potential of some NDa reduces.Fig. 6 C shows have parasitic capacitance CELWith internal resistance RELPicture
The more specifically equivalent circuit of element Gq.When the current potential of a NDa reduces, parasitic capacitance CELStart to put
Electricity (discharge current ic).By this electric discharge, the current potential of some NDb reduces as illustrated in fig. 6e.
Meanwhile, discharge current ic flows to organic EL element, anode current i and discharge current from a NDb
Ic flows into organic EL element.Therefore, when anode driver output signal occurs, current potential raises (crosses punching
And pixel Gq is the most luminous with brightness more higher than the brightness of original gradation OS),.In other words, figure
Each pixel in region AR2 shown in 4A has more higher brightness than original background gray value, and this may lead
Cause display uneven.
Therefore, if the pixel in different gray values drivings is present in same a line, and when cutting off relatively low ash
The driving of the pixel of angle value and when connecting the driving of the pixel of higher gray value, owing to cutting off relatively low gray value
Pixel after drive the pixel of higher gray value that waveform is produced impact immediately, luminosity changes.
Influence degree depends on the quantity of the pixel to drive with relatively low gray value.This is because turn from on-state
When the quantity of the pixel changing to dissengaged positions becomes big, current value change becomes greatly.
<correction process>
Uneven in order to eliminate the display of above-mentioned appearance, in the present embodiment, the data wire after correction is driven
Dynamic signal is previously applied to pixel, and otherwise these pixels are by with the Intensity LEDs higher than original gray value.Knot
Close Fig. 7 A to Fig. 8 D will correction process be illustrated.Based on scan line, a line scan line pixel is shown
Registration is according to being corrected.
Such as, Fig. 7 A schematically shows the view data of a frame.At the video data shown in Fig. 2 A
In memory element 32, the video data of a frame is stored.The video data of one frame is, such as, and 256 row
The data of × 128 row × 4 bits.Based on scan line, the video data of a frame is stored in shown in Fig. 2 B
Timing controller 44 buffer 52 in, based on point, (1 pixel=4, point=1 bit) will be aobvious
Registration is according to being supplied to selector 53.Therefore, as it has been described above, the gray value of each pixel of a horizontal scanning line
Corresponding objective count value exports from selector 53.
Parallel with this operation, checking list generative circuit 57 generates checking list, and is stored to checking list and deposits
In storage unit 58.Such as, Fig. 7 A schematically shows row La, Lb, Lc in a frame, and is every
The video data of row creates checking list.
In order to create checking list, first, checking list generative circuit 57 counts the display number at a horizontal scanning line
There is according to the video data quantity of same gray value.Specifically, checking list generative circuit 57 checks storage
The gray value of the video data of 256 pixels of horizontal scanning line in buffer 52, and count and sweep in a line
Retouch the video data quantity in line with corresponding gray value.Such as, at 256 of the row La shown in Fig. 7 A
Between the video data of individual pixel, the video data of 146 pixels has 8/15 gray value, 110 pictures
The video data of element has 2/15 gray value.Therefore, number of gray values table as shown in Figure 7 B it is created that.
Then, checking list generative circuit 57, by referring to inquiry table as shown in Figure 3 C, calculates Fig. 7 B
The correcting value that in shown count results (number of gray values table), each quantity of gray value is corresponding.Such as Fig. 7 B
Shown in, owing to the video data quantity of 2/15 gray value is 110, with reference to shown in Fig. 3 C, inquiry table obtains school
Positive quantity "-8 " (the pulse width correction amounts of corresponding-2 microseconds).Further, since 8/15 gray value is aobvious
Registration data bulk is 146, obtains correcting value "-12 " (corresponding-3 microseconds from inquiry table shown in 3C figure
Pulse width correction amount).
It addition, the correcting value that checking list generative circuit 57 is calculated by use creates checking list.Such as,
As shown in Fig. 7 E and Fig. 7 F, checking list includes gray value and the most corresponding count correction value.
Count correction value is the value representing objective count value correcting value.In practice, checking list can be by representing ash
4 bit binary data of angle value and the count correction value corresponding to each gray value are constituted.At Fig. 7 E and figure
In 7F, gray value file actually includes 4 bit binary data.It addition, Fig. 7 E and Fig. 7 F also shows
Go out the pulse width correction amount that count correction value is corresponding, but it is only for reference and need not be stored as school
Main schedule.
In the present embodiment, checking list generative circuit 57 is the most directly by based on each gray value in inquiry table
The correcting value that quantity obtains is used as the count correction value of corresponding gray value, and is used as than corresponding gray value
The correcting value (count correction value) of higher gray value.As it has been described above, this is because, if different ash
The pixel that degree drives is present in identical horizontal scanning line, and works as the driving of the pixel cutting off relatively low gray scale and connect
During the driving of the pixel of logical higher gray scale, the pixel of the relatively low gray scale of described cut-out can be the most immediately to relatively
The waveform of the pixel of high gray scale produces impact, and luminosity changes.
Specifically, in the example of count results shown in Fig. 7 B, correcting value "-8 " quilt of 2/15 gray value
It is set to the count correction value of 8/15 gray value.In this case, owing to not existing than 8/15 gray value
Higher gray value, does not has to use the correcting value "-12 " of 8/15 gray value.Thus be created that such as Fig. 7 E
Shown checking list.This table only has the count correction value "-8 " of 8/15 gray value.For 2/15 gray scale
For value, owing to there is not the gray value video data lower than 2/15 gray value, so not being corrected
(count correction value=0).
This is equally applicable to the row Lb shown in Fig. 7 A.Such as, by counting the video data of each gray value
Quantity obtains the quantity table of each gray value shown in Fig. 7 C, and obtains each gray value from inquiry table
Correcting value.Although illustrating, it is created that checking list in this case, wherein 6/15 gray value
Correcting value "-12 " is arranged to the count correction value of 12/15 gray value more higher than 6/15 gray value.
Row Lc shown in Fig. 7 A is the example of the scan line that wherein there are four different gray values.Due to right
The video data quantity of each gray value is counted, and is created that each gray value as illustrated in fig. 7d
Quantity table.Owing to the video data quantity of 1/15 gray value is 60, from inquiry table, obtain correcting value "-4 "
(being equivalent to-1 microsecond).Further, obtain respectively the correcting value "-4 " of 8/15 gray value, 10/15
The correcting value "-8 " of gray value and the correcting value " 0 " of 13/15 gray value.
Based on the above-mentioned checking list being created that as shown in Figure 7 F.More specifically, the correcting value of 1/15 gray value
It is arranged to the correcting value of 8/15 gray value, and the count correction value of 8/15 gray value becomes "-4 " (phase
When in-1 microsecond).For 10/15 gray value, the correcting value "-4 " of 1/15 gray value and 8/15
The summation of the correcting value "-4 " of gray value, i.e. "-8 " (being equivalent to-2 microseconds) is arranged to counting
Corrected value.For 13/15 gray value, the correcting value "-4 " of 1/15 gray value and 8/15 gray value
Correcting value "-4 " and the summation of correcting value "-8 " of 10/15 gray value, i.e. "-16 " (phase
When in-4 microseconds) it is arranged to count correction value.For 1/15 gray value, owing to there is not ratio 1/15
The gray value video data that gray value is lower, so not being corrected (count correction value=0).
It is that every horizontal scanning line creates checking list by this way, and stores it in the checking list shown in Fig. 2 B
In memory element 58.Then, following actual correction is carried out.It is similar to selector 53, showing of 4 bits
Registration is according to being sequentially supplied to selector 59.Therefore, selector 59 is from being stored in checking list memory element
The checking list of 58 reads the count correction value of gray value corresponding to 4 bits, and is output to addition
Device 55.Therefore, objective count value and count correction value are carried out being added as correction calculating by adder 55.
Carry out correction process for example, it is assumed that be currently expert on Lc, and the checking list shown in Fig. 7 F is deposited
Storage is in checking list memory element 58.In this case, when 4 bit data " 1000 " (=8/15 ash
Angle value) as pixel display data when buffer 52 is supplied to selector 53 and 59, selector 53
Reading " 80 " is as the objective count value (with reference to Fig. 3 A) of 8/15 gray value in gray scale chart, and selects
Select device 59 and read "-4 " as the count correction value (with reference to Fig. 7 F) of 8/15 gray value in checking list.
Then, objective count value " 80 " and count correction value "-4 " are added by adder 55, target meter
Numerical value is corrected as " 76 ".
As it has been described above, objective count value is corrected by count correction value, and it is transmitted to corresponding
Latch cicuit 60.The count value of objective count value with enumerator 61 is compared by comparator circuit 62,
To produce data wire driving signal.Here, due to the correction process that objective count value is carried out, data wire
Signal is driven to be corrected as the pulse width with reduction.Such as, if being created that school as shown in Figure 7 F
Main schedule figure, as shown in Figure 8 A, drives the pulse width of signal to carry out the data wire that each gray value is corresponding
Correction.More specifically, the pulse width of signal of driving of 8/15 gray value to be corrected to 19 from 20 microseconds micro-
Second, the data wire of 10/15 gray value drives the pulse width of signal to be corrected to 28 microseconds from 30 microseconds, and 13/15
The data wire of gray value drives the pulse width of signal to be corrected to 56 microseconds from 60 microseconds.
Fig. 8 B and Fig. 8 C shows and drives signal output (anode driver output signal) as data wire
The state that is reduced by correction of constant current.Such as, in the example of the row La shown in Fig. 7 A,
As shown in Fig. 7 B and Fig. 7 E, it is micro-that the data wire of 8/15 gray value drives the pulse width of signal to reduce 2
Second.Therefore, when driving the data wire of pixel of 8/15 gray value, as shown in Figure 8 B, anode drive
The pulse width of device output signal is former from the driving signal of 8/15 gray value (20 microseconds shown in Fig. 3 A)
Initial pulse width shortens 2 microseconds.It addition, in the example of the row Lb shown in Fig. 7 A, such as Fig. 8 C
Shown in, the data wire of 12/15 gray value drives the pulse width of signal to reduce 3 microseconds.Therefore, when driving
During the data wire of the pixel of dynamic 12/15 gray value, as shown in Figure 8 C, the arteries and veins of anode driver output signal
Rush the width original pulse width contracting driving signal from 12/15 gray value (50 microseconds shown in Fig. 3 A)
Short 3 microseconds.
By above-mentioned correction, it is suppressed that the pixel intensity that above-mentioned brightness may be caused to increase increases.In other words,
Even if occurring rushing OS, also inhibits, by correction, the brightness caused owing to excessively rushing OS increases, thus disappears
Remove or minimizing shows that the display on image is uneven.
Further, in the present embodiment, when objective count value is less and pulse width is less, do not hold
Row correction.As in fig. 8d, when the pulse width ratio predetermined threshold th1 that data wire drives signal is narrow,
Do not perform correction, and when it is wider than predetermined threshold th1, perform correction.When predetermined threshold th1 is such as
During 10 microsecond, the objective count value of 2/15 gray value, 1/15 gray value and 0/15 gray value is without carrying out school
Just.Therefore, in the gray scale situation that the time period applying electric current is originally the shortest, shorten apply electric current time
Between section be restricted.Further, in the present embodiment, when the objective count value of gray value is by correction
During decline, correcting value is defined so that the objective count value after correction goes above and follows corresponding ash closely
The objective count value of the gray value below angle value.
The above-mentioned process for realizing correct operation, specifically, will be in conjunction with Fig. 9, Figure 10 and Figure 11 couple
The process of corrected value signal generating unit 44a is described.This is mainly performed by checking list generative circuit 57
Process.
In step S101 of Fig. 9, checking list generative circuit 57 reads a line display number from buffer 52
According to.Because if all video datas of a horizontal scanning line are " 0000 ", it is not necessary to carry out school
Just, so checking list generative circuit 57 performs step S102 to step S105 to create all counting corrections
Value is the checking list of " 0 ".It is to say, in the checking list of checking list memory element 58, " 0 " quilt
Write is as the count correction value corresponding to each gray value (4 bit binary data), and this table quilt
It is set to the checking list of respective scan line.
Video data rather than the situation of gray value " 0000 " is there is in the video data of a horizontal scanning line
Under, checking list generative circuit 57 performs step S102 to step S103 to count each ash in this horizontal scanning line
The video data quantity of angle value.Therefore, the video data quantity of each gray value is counted, and
It is created that the quantity table of each gray value as shown in Fig. 7 B, Fig. 7 C or Fig. 7 D.Then, in step
In S104, by referring to inquiry table, checking list establishment proceeded as above.
Figure 10 and Figure 11 shows the processing example that step S104 is concrete.Except based on each number of gray values
The objective count value that count results is each gray value the process of count correction value, Figure 10 and Tu are set
Shown in 11, process includes, if the data wire of gray value drives the pulse width of signal equal to or less than predetermined
Threshold value, the process that the correction of gray value is limited, and the correction of the objective count value to gray value
The process that amount is defined so that after the correction of gray value, objective count value goes above and follows this gray value closely
The objective count value of following gray value.
In step S200 shown in Figure 10～S206, based on the number of gray values obtained in step S103
Table, obtains the correcting value corresponding to each number of gray values from inquiry table (seeing Fig. 3 C).First,
Checking list generative circuit 57 is in step s 200 by variable x reset-to-zero.This variable x be for 0/15～
15/15 gray value sequentially carries out the variable processed.Then, each gray value performs step S201～S204
Process, these gray values by increase variable x sequentially specify.
In step s 201, checking list generative circuit 57 is with reference in the quantity table being stored in each gray value
Count results inspection there is the video data quantity of x/15 gray value.If the display number of x/15 gray value
Data bulk is not " 0 ", then process proceeds to step S202 to obtain video data quantity from inquiry table
Corresponding correcting value.Then, in step S204, using correcting value as meter corresponding to x/15 gray value
Number corrected value writes in checking list temporarily.
Additionally, in this step, the count correction value being written in checking list (obtains from inquiry table
Correcting value) be not final count correction value.In step S204, Fig. 7 B, Fig. 7 C and Fig. 7 D institute
In the memory area showing in embodiment the correction value beyond table to be temporarily stored in as checking list to retain.Cause
This, effectively utilize for checking list retain memory area to store correcting value.
If it is determined that the video data quantity in step S201 is " 0 ", perform step S203, and will
" 0 " is set to the count correction value of x/15 gray value.This is because, if video data quantity is " 0 ",
Then there is no need to obtain correcting value from inquiry table.Then, in step S204, by count correction value (=0)
As in the count correction value write checking list that x/15 gray value is corresponding.
In step S205, determine whether variable x is 15, i.e. the most complete for all gray values
The process of correcting value is obtained from inquiry table.If variable x is not 15, then right in step S206
Variable x is incremented by, and repeats the process of step S201～S204.The correcting value of all gray values obtains
Take once completing, then perform step S205 to step S207.
In step S207～S211, checking list generative circuit 57 performs count correction value is write checking list
Process.As it has been described above, here, using the correcting value (or " 0 ") of acquisition in inquiry table as each ash
The count correction value of angle value is temporarily stored in checking list.Then, by for less than corresponding gray value
One or more correcting values that one or more gray values store temporarily carry out summation operation to obtain gray value
Final count correction value.In other words, as shown in Fig. 7 E and Fig. 7 F, the final counting of each gray value
Corrected value is the correcting value aggregate-value of gray value, and these gray values are less than corresponding gray value.In step
S207～step S212 perform to be set to count correction value the process of aggregate-value.
Checking list generative circuit 57 arranges variable x=15 in step S207.Then, on each gray value
Performing step S208～the process of S210, these gray values are sequentially specified by variable x.In this case,
This process is performed according to the order of 15/15 gray value～0/15 gray value.
In step S208, checking list generative circuit 57 checks in the quantity table being stored in each gray value
The video data quantity of x/15 gray value.If the video data quantity of x/15 gray value is " 0 ", then
The final count correction value of x/15 gray value is " 0 ".Here, 0 is written into as count correction value
Checking list (sees the process of step S203 → S204).Therefore, count correction value is write checking list
In it is not necessary that, perform step S211.
If the video data quantity of x/15 gray value is not " 0 " in step S208, i.e. if right
The video data of x/15 gray value performs correction and there is probability, performs step S209, and is x/15 gray scale
Value arranges count correction value.Specifically, in step S209, checking list generative circuit 57 obtains and compares x/15
The correcting value summation of any gray value that gray value is low, these gray values get from inquiry table.The most just
Being to say, relative to each gray value less than x/15 gray value, checking list generative circuit 57 will be stored as facing
Time count correction value correcting value (seeing the process of step S202 and step S204) be accumulated to checking list
In.
Then, in step S210, aggregate-value is finally write as the count correction value of x/15 gray value
Enter in checking list.Specifically, in checking list, it has been temporarily stored as x/15 ash with aggregate-value covering
The correction value (the correction value obtained from inquiry table) of the count correction value of angle value.Former for this
Cause, sequentially performs the process of step S208～S210, and the x/15 temporarily stored from 15/15 gray value
The correcting value of gray value is not used in obtaining the count correction value mistake of the gray value lower than x/15 gray value
Cheng Zhong.
In step S211, checking list generative circuit 57 determines whether variable x is 0, i.e. the most
The process obtaining count correction value is completed for all gray values.If variable x is not 0, then in step
Variable x is successively decreased by S212, and performs step S208.Therefore, step is performed for other gray value
The process of rapid S209 and S210.That is, first it is being that 15/15 gray value performs step S208～S210
After process, it is 14/15 gray value, 13/15 gray value in order ... perform step S208～S210
Process.
It addition, in the example of 0/15 gray value, owing to there is not the gray value less than 0/15 gray value,
And aggregate-value is 0, even if so the video data quantity of 0/15 gray value is not " 0 ", 0/15 gray scale
The count correction value of value also serves as in " 0 " write checking list.In other words, no matter 0/15 gray value is aobvious
Whether registration data bulk is " 0 ", and count correction value is set as 0.When completing the process of 0/15 gray value,
In step S211, determine that variable x is 0.Here, the count correction value of all gray values is written to school
In main schedule, therefore perform step S213 shown in step S211 to Figure 11 shown in Figure 10.
In step S213～S218, checking list generative circuit 57 equals to or less than predetermined threshold to gray value
Correction limit.
Specifically, checking list generative circuit 57 arranges variable x=0 in step S213.In step S214
In, checking list generative circuit 57 determines whether x/15 gray value is that equaling to or less than described in Fig. 8 D makes a reservation for
Gray value corresponding to the pulse width of threshold value th1.In another words, it is determined that whether x/15 gray value is without entering
Row correction.If it is not needed, then perform step S215, and by the count correction value of x/15 gray value
It is set to zero, in order to do not perform the correction of x/15 gray value.Then, in step S216, by x/15
In the count correction value write checking list that gray value is corresponding.Therefore, the count correction value of x/15 gray value is made
It is rewritten in checking list for " 0 ".
In step S217, determine whether variable x is 15, i.e. whether complete the place of all gray values
Reason.If variable x is not 15, then in step S218, variable x is incremented by, and from step S214
Repeat this process.
By step S213～the process of S218, force to be updated to " 0 " by the count correction value of gray value,
The gray value that this gray value pulse width equal to or less than predetermined threshold th1 is corresponding.Such as, if etc.
In or the gray value of the gray value corresponding less than the pulse width of predetermined threshold th1 be 2/15 gray value, 1/15
Gray value and 0/15 gray value, then at variable x=0,1,2 and the count correction value conduct of these gray values
" 0 " performs S215 and S216 in the case of being rewritten in checking list.Count correction value=0 means
Relative gray value is not corrected.
When completing the said process of all gray values and determining variable x=15 in step S217, perform
Step S219.
In step S219～S224, checking list generative circuit 57 is by target after the correction of x/15 gray value
Count value is limited to the objective count value more than the gray value followed closely below x/15 gray value.It is to say,
X/15 gray value carries out limiting the process (grey level compensation) of correcting value (count correction value) so that
After the correction of x/15 gray value, objective count value does not become equal to or less than following the ash below x/15 gray value closely
The objective count value of angle value.
Specifically, checking list generative circuit 57 arranges variable x=0 in step S219.In step S220
In, checking list generative circuit 57 checks the target meter by utilizing count correction value correction x/15 gray value
Whether numerical value and the value that obtains be equal to or less than the objective count value of (x-1)/15 gray value.For object count
For value, checking list generative circuit 57 is referred to gray scale chart.If it is equal to or less than (x-1)/15 ash
The objective count value of angle value, checking list generative circuit 57 in step S221 by the counting of x/15 gray value
Corrected value adds 1.
Owing to correcting value and count correction value are negatives as above, it is intended as counting so adding 1
The correcting value of corrected value reduces by a counting.Then, process returns to step S220, and checks by adopting
The value obtained by the objective count value of the count correction value correction x/15 gray value corresponding with correction for reduction amount
Whether equal to or less than the objective count value of (x-1)/15 gray value.
As it has been described above, in step S220 and S221, when objective count value after the correction of x/15 gray value
When equaling to or less than the objective count value of (x-1)/15 gray value, count correction value is adjusted (correcting value
Be defined) so that after correction objective count value be one more than following the gray scale below corresponding gray value closely
The counting of the objective count value of value.
When being completed the described adjustment of count correction value by step S221, checking list generative circuit 57 continues
Continue to step S222, and by the counting to x/15 gray value in checking list of the count correction value after adjusting
Corrected value is corrected.If it does not continue to S221, i.e. without necessity to x/15 gray scale
The count correction value of value is adjusted processing, then the most not counting school to checking list in step S222
On the occasion of being corrected.
In step S223, determine whether variable x is 15, i.e. the mesh to all gray values the most
Mark count value completes adjustment and processes.If variable x is not 15, in step S224, variable x is carried out
It is incremented by, and repeats this process from step S220.If variable x is 15, then terminate this process.
Process shown in Figure 10 and Figure 11 performs in step S104 shown in Fig. 9.In the process shown in Fig. 9
At the end of, the checking list of title scan line to be shown is retained in checking list memory element 58.Then,
As it has been described above, read out objective count value and count correction value by selector 53 and 59 for each pixel,
And the correction by adder 55 performance objective count value.
<sum up and change>
In the above-described embodiments, controller IC (display driver) drives display according to the gray value of pixel
The data wire DL of unit 10, and there is corrected value signal generating unit 44a and driving signal generating unit 44b.
The video data that corrected value signal generating unit 44a pixel on a horizontal scanning line SL is corresponding counts each ash
The video data quantity of angle value, and the video data corrected value (meter of each gray value is obtained according to count results
Number corrected value), thus generate checking list.
Driving signal generating unit 44b uses the count correction value being stored in checking list to objective count value
Perform correction process.Additionally, after described correction process, driving signal generating unit 44b is based on aobvious
Registration is generated data wire according to (objective count value obtained by adder 55) and drives signal every in order to drive
Data wire described in bar.By performing such correction, it is possible to the brightness disproportionation eliminating or reducing on display
And improve display quality.
Particularly, it is as noted previously, as by luminous gray scale or with the quantity of other light emitting pixel in a line
Impact, the signal being applied to pixel may cross punching.In the present embodiment, according to on a horizontal scanning line
In the video data that pixel is corresponding the video data quantity of each gray value determine video data to be corrected and
Correcting value.Therefore, it can the data wire to the pixel that may cause brightness disproportionation drives signal to carry out suitably
Correction.Specifically, correction can be performed in order to reduce the picture causing anode driver output signal to cross punching
The brightness of element, thus effectively eliminate or reduce brightness disproportionation.In other words, even if punching occurred, pass through
Its anode driver output signal of calibration response, it is possible to realize display with the brightness of original gray value.
Additionally, corrected value signal generating unit 44a obtains corresponding ash according to the video data quantity of each gray value
The correcting value of angle value, and by applying the school of corresponding gray value to the count correction value of corresponding higher gray value
Positive quantity is that each gray value generates count correction value.Be as noted previously, as the brightness flop that causes of punching according to
Video data quantity with gray value relatively low in a line affects the viewing area of higher gray value.Therefore, logical
The correcting value crossing each gray value that employing is obtained according to the video data quantity of each gray value realizes
Suitable correct operation, in order to obtain the correcting value (count correction value) of higher gray value.
In the present embodiment, corrected value signal generating unit 44a is according to the video data quantity of each gray value
Count results, shows corresponding between video data quantity and the correcting value of each gray value closing by use
The inquiry table of system generates corrected value.By by the video data quantity of each gray value and the correction of correspondence thereof
Amount storage, to inquiry table, can obtain, in conjunction with inquiry table, the school that the video data quantity of each gray value is corresponding
Positive quantity.
Therefore, it can the calculation process that is obviously promoted for determining correcting value and realize high speed processing.Separately
Outward, it is also suitably for sequentially creating the process of checking list based on scan line.Due to can be with above-mentioned simple electricity
Road generates at a high speed checking list, and every the line scanning can being synchronized with during scan line sequentially drives performs this process.
It is therefore not necessary to be pre-created checking list for often row, and store it in big memory area, such as,
In the frame of Unit one, thus circuit is caused to have advantage in terms of size.
Further, in the present embodiment, the perseverance configured so that having the corresponding grey scale value persistent period is carried out
Determining current signal drives signal to be applied to every described data wire DL as data wire.In this case,
Reduce the value of persistent period to store in inquiry table as correcting value.Signal is driven by data wire in order to tackle
Crossing the brightness increase that punching is caused, storage is for reducing the correcting value of constant current signal persistent period, sharp
Brightness is reduced with correcting value.Consequently, because by inquiry table is used as the constant current signal persistent period pair
The value answered, can generate count correction value easily, it is possible to realization is appropriate, and (persistent period subtracts
Correction less).
In the present embodiment, by the instruction from MPU2, the correcting value stored in inquiry table and display
One or both in data bulk is rewritable.Can change each according to the specification of display unit 10
Relation between video data quantity and the correcting value corresponding thereto of gray value.To this end, inquiry table quilt
It is configured to rewritable.Therefore, controller IC can be made up of chip, and it performs to meet dissimilar showing
Show the suitable correction of unit 10, and be adapted for use with universal component.
It addition, combined as described in step S213 shown in Fig. 8 D and Figure 11～S218, corrected value signal generating unit
44a does not has the aobvious of the gray value of the persistent period equal to or less than predetermined value to its data wire driving signal
Registration is according to performing correction process.In other words, by arranging count correction value=0, it is not corrected.Work as school
During the video data of the lowest gray value, low gray areas (such as, black display region) becomes the darkest.
For this reason, data wire drive the video data of the gray value that signal is corresponding be not corrected, should
Data wire drives signal to have the persistent period equal to or less than predetermined value, thus prevents the aobvious of low gray value
Show and become the darkest.
It addition, in trimming process, the correcting value of gray value is defined so that the correction of gray value
Rear objective count value goes above objective count value (Figure 11 step following the gray value below corresponding grey scale value closely
Shown in rapid S219～S224).Therefore, even if after calibration, it is also possible to guarantee the gray scale between gray value
Difference, and the difference between gray value can be maintained on display image.
Although below this embodiment being described, can display to the present invention set in every way
Standby and display driver is changed, and is not limited to above-described embodiment.Such as, it is used for performing Fig. 9, figure
The checking list generative circuit 57 of flow process shown in 10 and Figure 11 can be by operation processing unit (CPU etc.)
Or hardware configuration realizes.
Inquiry table memory element 56 and gray scale chart memory element 54 can be arranged on such as non-volatile memories
In the volatile memory area of device (flash memory) or such as D-RAM and S-RAM.Alternatively, in control
In the case of device IC processed is for being exclusively used in given display panel parts, inquiry table memory element 56 and gray scale chart
Memory element 54 can use ROM area.Although inquiry table has been used for creating checking list, Ke Yi
In the case of not using inquiry table, by predefined function computing, utilize the video data number of each gray value
Amount obtains correcting value.
Additionally, the flow process of Fig. 9, Figure 10 and Figure 11 is schematic.For example, it is possible to directly from inquiry
Table obtains the correcting value of each gray value, and does not perform the process of step S207 shown in Figure 10～S212.Enter
One step ground, can not perform the process of step S213 shown in Figure 11～S218, the most not to the persistent period
The gray value corresponding to signal is driven to be corrected equal to or less than the data wire of predetermined threshold.It is also possible to
Expect that step S219 shown in Figure 11～S224 not being carried out grey level compensation processes this example.
It addition, the present invention is applicable not only to use the display device of OLED, and it is applicable to other type
Display device.Such as, it is suitable for use with the display device of current drive-type self-emission device.
Although the present invention has carried out illustrating description in conjunction with described embodiment, but those skilled in the art
It is appreciated that on the premise of the scope of the invention limited without departing from the claims, can carry out
Variations and modifications.
Claims (6)
1., for driving a display driver for the data wire in display unit, described display unit includes
Data wire, every data line is commonly connected to the multiple pixels along column direction arrangement；Scan line, every
Scan line is commonly connected to the multiple pixels arranged in the row direction；And corresponding to described data wire and institute
State the pixel that each cross point of scan line is formed；Described display driver is according to the gray value of described pixel
Described data wire, described display driver is driven to include:
Corrected value signal generating unit, being used for based on scan line is corresponding to the display number of pixel in every scan line
Each described gray value counting video data quantity according to, and generate described display number based on count results
According to corrected value；With
Driving signal generating unit, for by using the corrected value generated by described corrected value signal generating unit
It is corrected described video data processing, and generates data wire driving letter based on the video data after correction
Number in order to drive every described data wire；
Described corrected value signal generating unit obtains correcting value according to the video data quantity of each described gray value,
And by using the correcting value of each described gray value obtained to generate the corrected value of described video data,
To calculate the correcting value of the gray value higher gray value more corresponding than the correcting value obtained；
Described corrected value signal generating unit is led to according to the count results of the video data quantity of each described gray value
Crossing use inquiry table to generate described corrected value, wherein said inquiry indicates each described gray value
Corresponding relation between video data quantity and described correcting value；
There is the constant current signal of persistent period corresponding to each described gray value as described data wire
Signal is driven to be applied to described data wire, and
Wherein, the correcting value being stored in described inquiry table is corresponding in order to the value shortening the described persistent period.
Display driver the most according to claim 1, it is characterised in that store in described inquiry table
Correcting value and video data quantity in one or both be rewritable.
Display driver the most according to claim 1, it is characterised in that described corrected value generates single
The video data with the gray value that the corresponding persistent period is more than threshold value only is corrected processing by unit.
Display driver the most according to claim 1, it is characterised in that described driving signal generates
Unit is corrected processing by limiting described correcting value so that the gray value of the video data after correction
Go above the value of gray value below the gray value corresponding to following the video data after correction closely.
5. it is used for according to a display drive method for the gray value driving data line of pixel in display unit,
Described display unit includes that data wire, every data line are commonly connected to the multiple pictures along column direction arrangement
Element；Scan line, every scan line is commonly connected to the multiple pixels arranged in the row direction；And it is corresponding
The pixel formed in each cross point of described data wire and described scan line, described display drive method bag
Include:
It is corresponding to each described gray value in the video data of pixel in every scan line based on scan line
Counting video data quantity, and the corrected value of described video data is generated according to count results；And
Process by using the corrected value that generated that described video data is corrected, and based on correction after
Video data generate data wire drive signal in order to drive every described data wire；
Video data quantity according to each described gray value obtains correcting value, and passes through what use was obtained
The correcting value of each described gray value generates the corrected value of described video data, to calculate than the school obtained
The correcting value of the higher gray value of gray value that positive quantity is corresponding；
The count results of the video data quantity according to each described gray value generates by using inquiry table
Described corrected value, wherein said inquiry indicates the video data quantity of each described gray value with described
Corresponding relation between correcting value；
There is the constant current signal of persistent period corresponding to each described gray value as described data wire
Signal is driven to be applied to described data wire, and
Wherein, the correcting value being stored in described inquiry table is corresponding in order to the value shortening the described persistent period.
6. a display device, including:
Display unit, including data wire, every data line be commonly connected to along column direction arrangement multiple
Pixel；Scan line, every scan line is commonly connected to the multiple pixels arranged in the row direction；And shape
Become with corresponding to described data wire and the pixel in each cross point of described scan line；
Display driver, for driving every described data wire according to the gray value corresponding to described pixel；
With
Scan line driver, for applying scanning signal to described scan line,
Wherein, described display driver includes:
Corrected value signal generating unit, being used for based on scan line is corresponding to the display number of pixel in every scan line
Each described gray value counting video data quantity according to, and generate described display number based on count results
According to corrected value；With
Driving signal generating unit, for by using the corrected value generated by described corrected value signal generating unit
It is corrected described video data processing, and generates data wire driving letter based on the video data after correction
Number in order to drive every described data wire；
Described corrected value signal generating unit obtains correcting value according to the video data quantity of each described gray value,
And by using the correcting value of each described gray value obtained to generate the corrected value of described video data,
To calculate the correcting value of the gray value higher gray value more corresponding than the correcting value obtained；
Described corrected value signal generating unit is led to according to the count results of the video data quantity of each described gray value
Crossing use inquiry table to generate described corrected value, wherein said inquiry indicates each described gray value
Corresponding relation between video data quantity and described correcting value；
There is the constant current signal of persistent period corresponding to each described gray value as described data wire
Signal is driven to be applied to described data wire, and
Wherein, the correcting value being stored in described inquiry table is corresponding in order to the value shortening the described persistent period.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2013-136376 | 2013-06-28 | ||
| JP2013136376A JP5771241B2 (en) | 2013-06-28 | 2013-06-28 | Display driving device, display driving method, and display device |
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| Publication Number | Publication Date |
|---|---|
| CN104252838A CN104252838A (en) | 2014-12-31 |
| CN104252838B true CN104252838B (en) | 2016-11-30 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5844368A (en) * | 1996-02-26 | 1998-12-01 | Pioneer Electronic Corporation | Driving system for driving luminous elements |
| CN1424707A (en) * | 2001-11-21 | 2003-06-18 | 佳能株式会社 | Display device, image signal controller and driving controller thereof |
| TWI301265B (en) * | 2004-01-27 | 2008-09-21 | Richtek Techohnology Corp | |
| JP4316915B2 (en) * | 2003-04-04 | 2009-08-19 | Ｔｄｋ株式会社 | Image display apparatus and driving method thereof |
| CN102016968A (en) * | 2008-11-28 | 2011-04-13 | 卡西欧计算机株式会社 | Driving device for organic electroluminescent pixel and light emitting device |
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5844368A (en) * | 1996-02-26 | 1998-12-01 | Pioneer Electronic Corporation | Driving system for driving luminous elements |
| CN1424707A (en) * | 2001-11-21 | 2003-06-18 | 佳能株式会社 | Display device, image signal controller and driving controller thereof |
| JP4316915B2 (en) * | 2003-04-04 | 2009-08-19 | Ｔｄｋ株式会社 | Image display apparatus and driving method thereof |
| TWI301265B (en) * | 2004-01-27 | 2008-09-21 | Richtek Techohnology Corp | |
| CN102016968A (en) * | 2008-11-28 | 2011-04-13 | 卡西欧计算机株式会社 | Driving device for organic electroluminescent pixel and light emitting device |
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